A New Peak Detection Method for Single or Three-Phase Unbalanced Sinusoidal Signals

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A New Peak Detectio Metod for Sigle or Tree-Pase Ubalaced Siusoidal Sigals Jusog Rim 1,3, Colyog Ri 1, Hogcol Ji 2, Colji Or 3, Colju Rim 3, Hyewo Ri 2 1. Departmet of Pysics, KimIlSug Uiversity, Pyogyag, DPR of Korea 2. Departmet of Termal Egieerig, KimCaek Uiversity of tecology, Pyogyag, DPR of Korea 3. Departmet of Cotrol Sciece, Uiversity of Scieces, Pyogyag, DPR of Korea 1 Abstract- I tis paper, a fast amplitude detectio metod for te sigle or tree-pase ubalaced siusoidal is reported. Te proposed metod is a metod of te amplitude detectio for a sigle pase or tree pase ubalaced siusoidal sigal, based o detectig of te pulse widt correspodig to te peak amplitude. Te detectio period is te alf period of te iput sigal. Tis metod is idepedet of te tree-pase sigal s ubalace ad pase sequece. Te proposed metod was verified troug experimets for te sigle or tree-pase ubalaced sigals. Idex Terms Amplitude detectio, detectio, fast amplitude detectio, ubalaced tree-pase sigals T I. INTRODUCTION HE developig of electrical/electroic tecology, it s ecessary to estimate more quickly electrical parameters i sigle or tree-pase applicatios. Te fudametal voltage, curret, ad pase agle are very importat i power system. Te siusoidal amplitude detector is broadly used i electrical processes suc as power system moitorig, protectio ad fault detectio. I particular, voltage sag detectig teciques iclude te root mea square (RMS, Fourier trasform, ad peak voltage detectio metods [10]. I some cases, tree-pase ubalace is occurred because of several reasos i te tree-pase system, so i real applicatio process eeds fast peak detectio for te tree-pase ubalaced sigal. Several metods [1, 2] proposed to improve te respose time of sigle-pase siusoidal amplitude detectio. Some researces [8, 9, 16] proposed te peak amplitude detectio metod by te usig of pase-locked loop. Ad also tere are rapid peak detectio metods based o a oliear adaptive filter [10], a modified Proy s model [15], ad fast voltage sag detectio metod based o peak detectio [19]. Tree-pase systems are widely used i te idustry power system. Te tree-pase peak detectors ave bee developed [3,4], wic ca measure te peak value of tree-pase siusoidal sigals by te usig of tree pases of voltage. Te ig speed measure metod by te usig of two pases of voltage was proposed [5, 6]. However, tese metods ca oly be used i balace state ad as deviatio i ubalace state. Recetly, several teciques ave bee proposed te fast detectio metods of amplitude, pase ad ubalace parameters i tree-pase systems, suc as tree-pase sytetic testig wit asymmetrical sort-circuit currets[7], tree-pase tree-agle algoritm (TP TA[11], metod usig a modified all-pass filter (MAPF [12], metod for te lie-iteractive dyamic voltage restorer (DR[13], paselocked-loop (PLL circuit based o te p-q teory[14], low-pass otc filter PLL (LPN-PLL[17], Maximum Likeliood Estimators (MLEs[18]. I tis paper, a ew peak detectio metod for te sigle or tree-pase ubalaced siusoidal sigal is proposed. Te proposed metod is based o detectig of te pulse widt correspodig to te peak amplitude. Te detectio period is te alf period of te iput sigal. Ad te proposed metod is idepedet of te pase sequece ad ubalaced coditio ad ca be also used i te sigle or tree -pase tree wire ad tree-pase four wire. Te performace of tis metod is demostrated by a real electroic circuit. II. METHOD OF DETECTING THE PEAK AMPLITUDE Te siusoidal sigal is geerally siged as follows. t (1,were t ( ( p si( t is istataeous value of iput sigal, P is te maximum amplitude ad is te agular frequecy of te siusoidal sigals. From ere, is P t ( p ( t si( t (2 If we fix at te measure momet as ( t i te measure circuit, will be idicated as follows P Fig. 1. I te case of te same frequecy ad te pase cage of te same voltage lie variatio.

2 p si( t (3 I were te will be a costat depedet o te measure circuit, t is te time tat iput sigal takes from zero cross poit to value. From ω=2πf, if we kow te frequecy f of system ad time value t, we ca easily calculate Fig. 1 sows te cage of t i te siusoidal sigal of te differet amplitude i te fixed frequecy. Usig comparator ca realize te amplitude fixig of iput sigal.(fig. 2 Te sigal obtaied from multiplier process of te up alf period ad dow oe of iput sigal is (b i Fig. 4. Tis pulse widt flows i proportio wit t. I case of tree-pase sigal, pulses of every pase sigal pass te add circuit. Te output sigal is te pulses row as te output of Fig. 10 because te zero-cross momets of every pase sigal are differet. From te above, we do t use te rectifier ad AD coverter. P. To implemet te proposed metod writte as equatio (3 by a electroic circuit, we ave to measure f ad t togeter at a alf period of siusoidal sigals. t appears twice at eac alf period sigal (te begi ad te ed of alf period sigal ad wit t of te before alf period sigals ad later oe. Ad ave to detect te zero cross. Tus we compose te iput circuit wit a opt coupler to isolate iput/output, improve te repeat caracteristic witout detectig of te zero cross. Te iput resistor ad te collector s bias resistor of te optocoupler are selected by te iput voltage rage ad te liear caracter of te optocoupler. Fially, a pulse wit t at is obtaied as result of multiplyig two sigals from te aalog comparator coected wit te optocoupler. Te tresold of te comparator is i te liear rage of te optocoupler s output sigal. We iput tis sigal to te capture iput of te micro cotroller ad measure ad t, calculate P value. (Fig.3, 4 Fig.5 sows te detectio block of te peak amplitude i te tree pase siusoidal sigal.tis metod ca apply to all of tree pase tree wire ad tree pase four wire wit cage of te iput isolatio circuit. f Fig. 2. Block diagram of te proposed metod i te sigle pase. Ad we detect ad t of every alf period to calculate te peak amplitude. Due to te idepedece of measure, peak amplitude value of tree pase sigal is ot iflueced from te oter pase i te measure ad tis measure metod ca be also used i te tree pase tree wire ad tree pase four wire. f III. HARDWARE IMPLEMENTATION Fig. 4. Te relatio betwee iput siusoidal sigal ad output pulse sigal. Fig. 3. Detect block of te sigle pase siusoidal amplitude

3 Fig. 5. Detect block of te tree pase siusoidal amplitude Te part of mai circuit is same as a sigle pase detectig circuit. But te output pulse of obtaied eac pase, after is processed by te adder circuit, is iputted to te capture iput of processor. Also iput pulses of tree pase sigal iput to te processor to idetify te pase, wic make it possible to calculate voltage ad pase agle of eac pase respectively. If a detectig circuit is composed as tis, we ca calculate te amplitude of eac pase sigal ad te ubalace coditio of iput sigal,idetify te pase sequece cage, te pase cuttig, te pase sort from detectig of te pase agle variatio. I. TEST RESULT A. Liearity To test te liearity of te proposed detector, we tested a sigle-pase voltage. Fig.6 sows te test result. Te solid lie is teory value, ad te dotted lie is te measured result. To decrease te calculatig time, use te approximatio. From ωt<<1, (3 is caged as t si( t (4 p A (5, were A is a costat. Altoug te use of approximate calculatios, te detector appears good results i te iput voltage of 50 ~ 440 rage. Te error voltage is less ta 0.2 i te most of rage ad is less ta 0.5 i te boudary poit. Te error mostly relates wit te accuracy of frequecy detectig i te processor ad te approximatio. Tis sows tat te proposed detector as te sufficiet liearity i real applicatio. B. Frequecy Caracteristic Fig. 7 sows te test result of frequecy caracteristic i te proposed detector. Te frequecy of iput sigal is 31~300Hz ad is tested i te certai voltage. Test result sows tat tere is ot te cage of voltage i te error rage. Te reaso of error is same as before. Tis sows tat te proposed metod is idepedet of te frequecy caracteristic. C. Effect of pase sequece Fig. 8 sows te wave form of output sigal i te proposed metod we te pase sequece is caged. Te pase sequece of Fig. 8(a is a b c ad Fig. 8(b is b a c. As kow as Fig. 8, i te case of te cage of te pase sequece, te sequece of pulse row iputtig to capture iput of te processor is caged, but tere is ot a variatio of te peak Fig. 6. Te liearity of te proposed metod Fig. 7. Te frequecy caracteristic of te proposed metod

4 Fig. 8. Te effect of te pase sequece i tree pase sigal detectig. amplitude i te correspodig pase. Because te proposed metod determiates te peak amplitude value from ceckig of te sequece of iputtig pulse arrage, immediately detects te cage of te pase sequece. Te result sows tat te proposed metod is idepedet of te pase sequece ad ca detect te cage of pase sequece togeter. D. Respose Caracteristic Te proposed metod ca detect te correspodig peak amplitude of pase i eac output pulse. Accordigly te detectio period is te alf period of te iput sigal. (Fig. 4 E. Effect of Harmoics Fig. 9 sows te test result of te effect of armoics. (a is te output pulse sigal witout armoics, (b is wit armoics, (c is wit usig of LPF i te iput of detector ad aalog comparator. I tis metod, te removal of armoics effect is importat because we calculate te peak amplitude from measurig te output pulse widt. Tis problem ca be solved by usig of a pre-filter i te iput of tis detector ad a low-pass filter i te iput of aalog comparator, te software process. Tis paper proposes te tecique tat ca cacel te effect of waveform distortio about te zero cross by measurig te iterval betwee te times we te sigal reaces te tresold i te first ad te secod alf-periods, but ot by measurig te iterval betwee te zero cross ad te time we te sigal reaces te tresold i eac alf-period. (Fig.4 I te proposed metod a pre-filter ad a active low-pass filter are located at te before ad after of te optocoupler to cacel te effect of te armoics, uses te digital processig to cacel te parasitic vibratio occurred at te before ad after of te mai pulse waveform. If te armoic distortio is too large, a active power filter may be iserted ito te iput to cacel te armoics ad distortios. F. Effect of ubalace We te tree-pase system is ubalace, it may iclude pase ubalace, amplitude ubalace, or bot. I amplitude ubalace, tree-pase sigal ca be represeted as t (6 ( ( 1 si( t A P ( t ( P 2 ( t ( P 3 si( t 120 B (7 si( t 120 C (8, were, ad are tree-pase amplitude error 1 2 3 sigal. I tis metod, t value is accordig to amplitude value i eac pase sigal.(fig. 10 Tus, tis metod ca detect te ubalaced amplitude of eac pase respectively ad detect te ubalaced state. I pase ubalace, A t si( t (9, were 1 ( P 1 ( t P si( t 120 2 ( t P si( t 120 3 B (10 C (11, ad 2 3 are eac pase deviatios. I tree-pase 3 wire, A( t, B ( t, C ( t are sigals betwee AB, BC, CA, te pase ubalace is represeted as amplitude cage of (6, (7, (8. I tree-pase 4 wire, because te deviatio value is icluded to t value, amplitude cage is ot matter to pase ubalace. Tis sows tat te proposed metod is idepedet of te tree-pase ubalace. Fig. 9. Effect of armoics i te proposed metod Fig. 10. ariat of output pulse widt i ubalace coditio

5. CONCLUSION I tis paper,a fast amplitude detectio metod for te sigle or tree-pase ubalaced siusoidal sigal was preseted. Te proposed metod is a metod of te amplitude detectio for a sigle pase or tree pase ubalaced siusoidal sigal, based o detectig of te pulse widt correspodig to te peak amplitude. Te detectio period is te alf period of te iput sigal. I tis metod, te sigle pase peak detectio metod is applied to te peak detectio of tree-pase siusoidal sigal. Tis metod is idepedet of te pase sequece ad ca detect te cage of pase sequece immediately. Ad tis metod is idepedet of te tree-pase sigal s ubalace. Te proposed metod as to detect te frequecy of te iput sigal ad eeds aalog filter or digital filter because it depeds o te sigal armoics. [14] F. Liccardo, P. Mario, ad G. Raimodo, Robust ad Fast Tree-Pase PLL Trackig System, IEEE Trasactios o Idustrial Electroics, ol. 58, No. 1, Ja. 2011 [15] Ceg-I Ce ad Gary W. Cag, A Efficiet Proy-Based Solutio Procedure for Trackig of Power System oltage ariatios, IEEE Trasactios o Idustrial Electroics, ol. 60, No. 7, July. 2013 [16] W.-C. Lee, T.-K. Lee, Peak Detectio Metod Usig Two-Delta Operatio for Sigle oltage Sag, Iteratioal Power Electroics Coferece 2014, pp. 595-600. [17] Kyoug-Ju L., Jog-Pil L., Dogsul S., Dog-Wook Y. ad Hee-Je K., A Novel Grid Sycroizatio PLL Metod Based o Adaptive Low-Pass Notc Filter for Grid-Coected PCS, IEEE Trasactios o Idustrial Electroics, ol. 61, No. 1, Ja. 2014 [18]. Coqueuse, A. Beloucrai, E. H. E. Bouciki ad M. E. H. Bebouzid, Estimatio of Amplitude, Pase ad Ubalace Parameters i Tree-pase Systems: Aalytical Solutios, Efficiet Implemetatio ad Performace Aalysis, IEEE Trasactios o Sigal Processig, ol. 62, No. 16, August 15,2014 [19] Y. Sillapawicar, A Fast oltage Sag Detector Based o Peak Detectio, i Proceedigs of ECTI-CON 2015. ACKNOWLEDGMENT Te autor wises to tak te IEEE for providig tis template ad all colleagues wo previously provided tecical support. REFERENCES [1] H. L. Jou, H. Y. Cu, C. L. Huag ad C. H. Ce, A sortest data widow algoritm for detectig te peak value of siusoidal sigals, IEEE Trasactios o Idustrial Electroics, ol. 37, Oct. 1990, pp. 424-425. [2] H. Y. Cu, H. L. Jou, ad C. L. Huag, Trasiet respose of a peak voltage detector for siusoidal sigals, IEEE Trasactio Idustrial Electroics, ol. 39, No. 1, Feb. 1992, pp. 74-79. [3] Cig-tsai P. ad Mao-Ci J., A quick respose peak detector for variable frequecy tree-pase siusoidal sigals, IEEE Trasactios o Idustrial Electroics, ol. 41, No. 4, August. 1994, pp. 434-440. [4] Mao-Ci J. ad Cig-tsai P., Fast peak detector for variable frequecy tree-pase siusoidal sigals, IEE proceedigs Circuits Devices ad Systems, ol. 141, 1994, pp. 151-156. [5] Kue-Der W. ad Hurg-Liag J., A New Peak Detectio Metod for te Tree-Pase Siusoidal Sigals, IEEE Trasactios o Idustrial Electroics, ol. 45, No. 4, August. 1998, pp. 579-584 [6] Kue-Der W. ad Hurg-Liag J., A Ortogoal Peak Detector for Multipase Siusoidal Sigals, IEEE Trasactio o Istrumetatio ad Measuremet, ol. 49, No. 6, Des. 2000, pp. 1216-1223. [7] D. Dufouret, G. Motillet, Tree-Pase Sort Circuit Testig of Hig-oltage Circuit Breakers Usig Sytetic Circuits, IEEE Trasactios o Power Delivery, ol. 15, No. 1, Jauary 2000. [8] T. J. Yamaguci, M. Soma, M. Isida, T. Wataabe, ad T. Omi, Extractio of Istataeous ad RMS Siusoidal Jitter Usig a Aalytic Sigal Metod, IEEE Trasactios o circuits ad systems-ii: Aalog ad Digital sigal processig, ol. 50, No. 6, Jue 2003 [9] M. Karimi-Gartemai, H. Karimi, ad M. Reza Iravai, A Magitude/Pase-Locked Loop System Based o Estimatio of Frequecy ad I-Pase/Quadrature-Pase Amplitudes, IEEE Trasactios o Idustrial Electroics, ol. 51, No. 2, April. 2004 [10] R. Naidoo ad P. Pillay, A ew metod of voltage sag ad swell detectio, IEEE Tras. Power Del., ol. 22, No. 2, Apr.2007, pp.1056 1063 [11] M. Madrigal ad B. H. Roca, A Cotributio for Caracterizig Measured Tree-Pase Ubalaced oltage Sags Algoritm, IEEE Trasactios o Power Delivery, ol. 22, No. 3, July 2007 [12] S. Lee, T.-K. u ad H. Ca, A New Fast Peak Detector for sigle or Tree-Pase Usymmetrical oltage Sags, IEEE Eergy Coversio Cogress ad Expositio (ECCE 2010, 2010, pp. 434-440. [13] B. Bae, J. Jeog, J. Lee, B. Ha, Novel Sag Detectio Metod for Lie-Iteractive Dyamic oltage Restorer, IEEE Trasactios o power delivery, vol. 25, NO. 2,.APRIL 2010, pp 1210-1211.